Magnetic shielding design and analysis for wireless charging coupler of electric vehicles based on finite element method

To reduce the operating electromagnetic interference of the wireless charging coupler in the non-working area and increase its coupling efficiency, this paper focuses on the space electromagnetic energy constraints and designs an energy coupler with magnetic shielding. A finite element model of the coupler is built. Both the simulation results and the experiment data prove the feasibility of the proposed structure. The results indicate that, after installing the ferrite shield out of the coupling structures, the magnetic field is concentrated within the area between the transmission coil and the receiver coil and the magnetic field distribution is more homogenized. The magnetic field density out of the magnetic shielding is far less than that without magnetic shielding. So the radiation loss is reduced. By adding the magnetic shielding components, the inductance of the coupling structure is increased and its resonant frequency is then decreased. Therefore, the structure would improve the system transfer efficiency under poor coupling conditions of long separation and horizontal misalignment. It can also reduce the electromagnetic interference of electric vehicles'wireless charging and improve the system operational stability.